An update to the commenting system will be coming to threads on sport articles and blogposts today. The new system shows responses directly below the original comment – known as "single-line threaded comments". Replies between posters are grouped together or "nested" in the stream of comments, so they can be read in one place and users can navigate conversations more easily.

You will also notice that the report, reply and share buttons now appear when you hover over them. The colour and placement of the Guardian Pick and recommend buttons have also changed.

We plan to monitor how the new features affect comments, communities and conversations. Let us know what you think.

Here are a few questions that have been answered on a previous thread:

We have received a lot of questions about the new commenting platform, which is now live on a selection of threads on news articles and blogposts. Here is a selection of some of the Frequently Asked Questions as answered by Julian Fitzell and the Discussion team:

Will there be an option to switch between the old and the new version? - TheThistle

We've talked about having an option and at the moment it's not an option we're considering. The primary reason is that our research shows that conversations develop differently when people are viewing them threaded (for example, people may tend to post two shorter comments on different topics rather than one bigger one or may be less likely to reply to an unrelated comment)—we don't want to muddle the conversation by having two styles in play at the same time.

We're comfortable that the overall experience is an improvement with the new changes, even though we know there are some cases that aren't handled as well. We'll be looking at what we can do to improve those going forward, and we'll be doing that the same way as all our other changes by using data and testing to confirm positive result

What research was carried out? - lesbitches

A/B testing is something we do pretty regularly, though we find it's better suited to smaller changes than this. For larger changes, we tend to use more qualitative methods first to dig deeper and then use comparative metrics before and after, which gives us a pretty clear idea of the impact of the change.

Our development process involves looking at data (usage statistics, surveys, etc), going out to coffee shops and asking random people to try prototypes, working with usability experts, running qualitative user testing groups, answering emails from readers, and so on. It's not like we just sent out a survey that we can share statistics from.

We interviewed current readers of posts as well as commenters and asked questions about what people value about the site as well as presenting various options for displaying comments.

We also tested the nested format across the site and examined comment numbers and quality, disregarding threads like this one which focused on discussing the new format rather than the ATL content. The results indicated that the nested format on average generated more comments and less abuse than the linear format.

We're examining ways to surface quality comments though as Julian says measuring quality is not straightforward.

there were also tests conducted on the site, with regular commenters involved on Books and Music in February and March. I realise this has been mentioned before, but more details of that can be found here here. Those sections were chosen as a way to get representative feedback, it explains:

firstly we know we already have some excellent community interaction in those sections on content like Readers Recommend, Poster poems and the regular Tips, links and suggestions thread.

What will you do with the feedback here? - MegaShark

Everything we do factors in public opinion (not exclusively, obviously, we are a business not a democracy) and this is no exception. It's of no direct benefit to the Guardian that the comments are threaded; this change was made in response to a strong expression from our reader community that it presents a better comment experience.

We look at what people say, their usage patterns on the site, and so on, as well as doing surveys, user testing groups, focus groups, and so on. And we will continue to do so, so we'd love you have your (constructive) thoughts.

And adds:

We'll certainly be watching them but we won't be rushing to make any changes until the initial waves settle and we can get an accurate sense of the impact. At that point, I'll ask if someone can do a blog post about some of the results. You'll also get a pretty good sense whether the stats back up our hypotheses, though, just by watching the evolution of the system.

Does the new system slow down the page? - equusmulusoctopus

The new comment platform is a completely new system, and that was done largely for architectural/performance reasons, so we're actually expecting better performance. We will definitely see more requests overall, because the old system was returned in a single request where the current one makes several browser requests for different pieces of data, but they're different kinds of requests. Comparing a single metric between the two systems is like apples and oranges—we're happy with our scaling so far.

At the moment there isn't a way to 'close a nest' - so you should be able to click through past pages and see anything you think you've missed - or you'll just see them on the page you're looking at when you refresh.

We plan to allow you to collapse/expand threads, yes. We actually had it nearly implemented but had to turn it off because some other changes to the system broke it. We'll get back to finishing that off as soon as we have time.

We have all the timestamp data, so technically any ordering is possible, but we don't currently have plans to support a linear view in parallel (I've explained in another comment why not).

Is there a way to see which comment is replied to in a particular thread? - equus

Thanks for your suggestion about putting the "in response to" captions back, though. That's certainly something we could look at doing if people find it helpful. The original plan was to have the user's name link back to or highlight the comment being replied to, but we haven't had time to implement that yet. I agree it could be clearer than it is now...

I can't see the 'read all comments' button - is this part of the new system?

Will you ever go beyond a single line of threading? - kizbot

The single level of threading is a bit of a compromise and one that we're definitely watching carefully. Having unlimited levels of threading offers its own set of problems. From what we've seen so far, when a thread branches off, it tends to be focused enough on a single topic that the chronological ordering works ok. But as I said, we're keeping an eye on this and this is definitely an area where feedback is helpful. If there's a strong call that two levels would be better, it's certainly something we could look at user testing.

How will you measure if this 'works'?

The short-term plan is to show only the first N (where N is yet to be determined) replies to a comment by default, with an option to expand or collapse all of the threads on a page. Longer term, we hope to do some work on quality metrics, which will help surface good content and drop "first posts".

we'll have to keep a close eye on how threading changes/improves/alters/affects/frustrates both different communities on the site and different types of article and discussion (e.g. live blogs, Q&As, blog posts, open threads) and make sure that the development team are being made aware of how it's going down.